reproduction

Introduction

reproduction, capacity of all living systems to give rise to new systems similar to themselves. The term reproduction may refer to this power of self-duplication of a single cell or a multicellular animal or plant organism. In all cases reproduction consists of a basic pattern: the conversion by a parent organism of raw materials from the environment into offspring—or into cells that develop into offspring (see meiosis; mitosis)—of a constitution similar or potentially similar to that of the parent. The reproductive process always includes the transmission of hereditary material (see nucleic acid) from the parents so the offspring too can reproduce themselves. Although the methods and complexity of the reproductive process vary tremendously, two fundamental types may be distinguished; asexual reproduction, in which a single organism separates into two or more equal or unequal parts; and sexual reproduction, in which a pair of specialized reproductive (sex) cells fuse.